From: "John S. Fine" Newsgroups: comp.os.msdos.djgpp Subject: Re: Optimizations Date: Sun, 20 Sep 1998 13:01:34 -0400 Lines: 30 Message-ID: <360534EE.4241@erols.com> References: Reply-To: johnfine AT erols DOT com NNTP-Posting-Host: 207-172-240-213.s22.as4.bsd.erols.com Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit To: djgpp AT delorie DOT com DJ-Gateway: from newsgroup comp.os.msdos.djgpp Precedence: bulk Eli Zaretskii wrote: > > I saw nothing relevant and nothing that addressed the > > NOPs inserted for alignment. > > How about -m386 and -m486? In 2.7.2.1 -m386 had no effect (I assume it is the default). -m486 only made things worse. It changed the alignment from 2 to 4. (I finally noticed the -malign switches. I had been looking under optimization switches rather than under Intel 386 switches). It changed every "leave" to "mov %ebp,%esp pop %ebp". It changed every push of a memory location to a mov to a register followed by a push of the register (even when that use of a register made nearby code worse for lack of a register. I changed to 2.8.1 (I may be looking for advice on changing back). It generated slightly worse code. The -m386 -m486 and even -mpentium switches now make no difference at all. I must be doing something wrong, but I can't guess what it is. -- http://www.erols.com/johnfine/ http://www.geocities.com/SiliconValley/Peaks/8600/